温度自动补偿超磁致伸缩材料布拉格光栅光纤电流传感器

基于超磁致伸缩材料,提出了一种传感光纤光栅(S-FBG)和参考光纤光栅(A-FBG)相结合的温度自动补偿全光纤交流电流传感器。此传感器将传感光纤光栅和参考光纤光栅级联呈"十字形"后粘贴在超磁致伸缩材料上,然后将其置于聚磁回路狭缝内;同时控制传感光纤光栅的径向与磁场方向相同,而参考光纤光栅的径向与磁场方向相反。最后,将S-FBG的中心波长置于A-FBG反射谱的边带上,通过检测两光纤光栅级联反射光强的变化实现了电流测量及温度自动补偿。选用3dB谱宽分别为0.23nm和0.08nm的A-FBG和S-FBG进行了实验测试,结果表明:有效安匝电流为1.0~138.2A时,该传感器可实现线性测量,线性度为0.996 3,测量灵敏度为16.0 mV/A,最小可测有效安匝电流为1.0A。

Temperature compensated GMM-FBG current sensor

Based on Giant Magnetostritive Materials(GMMs), a novel GMM-FBG (Fiber Brager Grating) current sensor with automatic temperature compensation is proposed by combing a sensing fiber Bragg grating (S-FBG) and an auxiliary fiber Bragg grating (A-FBG). The sensor cascades the S-FBG and the A-FBG and pasts them crossly on the GMM bars, then puts them into a magnetic circuit consisted of the ferrites. The radial direction of S-FBG is controlled the same as the direction of magnetic field, and that of the A-FBG is opposite with the former. Finally, the center wavelength of S-FBG is placed in the side-band of A-FBG spectrum, and current measurement and temperature compensation are implemented by detecting the optical intensity variation of cascaded gratings. The experiments are performed by the A-FBG and S-FBG with the 3 dB band width of 0.23 nm and 0.08 nm. The experimental results show that when the ampere-turns-current varies from 1 A to 138.2 A, the sensor can realize the linear measurement, and the goodness of fit is 0.996 3, the sensing sensitivity in the linear range is 16.0 mV/A and the minimum effective ampere-turn is 1.0 A.